Luscious flavors and gorgeous colors are just some of the appealing traits of heirloom crops. And if you’re among the ever-growing number of people who love having them on their plates, you can thank the Seed Savers Exchange, a seed bank that’s been keeping more than 20,000 varieties of heirloom vegetables, fruit and flowers available since 1975.

Seed Savers’ collection is a treasure trove for gardeners and foodies who want what you can’t find anywhere else. “We give access to the world,” says Rosalind Creasy, a Seed Savers board member and Los Altos garden designer. “Many seeds are old varieties that have been passed down from generation to generation. If your grandpa grew something in Estonia, chances are it’s in our collection.”

As one of the few seed banks in the country that offers seeds for the home gardener, Seed Savers has an 890-acre headquarters in Iowa where they research, trial and keep extensive data on everything they grow. Its network of 13,000 members around the world helps save and strengthen thousands of crops to protect their existence and our food supply. Creasy has been involved with Seed Savers almost from the start. As the nonprofit celebrates its 40th anniversary, she weighs in on why their work is as important as ever.

Q: How did you get involved?

A: In 1982, I was catapulted into the national media scene when I wrote “The Complete Book of Edible Landscaping,” which is about designing gardens with food crops, an idea that was revolutionary at the time. While touring the country for my book, I kept meeting people who talked about varieties I’d never heard of, like purple beans and blue potatoes. As a longtime environmental activist, I realized it’s not just wild things that need to be saved — it’s domesticated species, including food crops, too. Once I learned about Seed Savers, I jumped in.

Q: How does the “exchange” part of Seed Savers Exchange work?

A: We publish an annual print and digital yearbook that members can look through to share open-pollinated seeds with other members. They then grow the plants to compare how they (grow) in different parts of the country and around the world. All we ask is that they save the seeds of what they grow and make them available through the exchange.

Q: So, the point is not just to preserve the seeds, it’s also to keep them growing in a range of locations?

A: Yes. We want these out there in different climates so we keep selecting the strongest ones — it’s not a static process. Plants are evolving. We’re seed detectives — we find out what does well where. If I save seeds from my healthiest 'Christmas’ lima beans, and do that year after year, those limas become adapted to Los Altos and to my garden.

Q: Why is it important to save so many kinds of seeds?

A: It’s a safety net for the future. This generation’s legacy to the next is to preserve a huge array of genes for our own food security. We’re now identifying varieties that can take different levels of heat, humidity and other conditions, and our human ecosystem needs this kind of plant diversity in order to survive all types of pests, diseases and climate change. Are we going to die if there’s no cabbage in the world? No. But if the entire cabbage family (which includes broccoli, cauliflower, kale and more) is gone, then we have a problem.

And it’s for the flavor, damn it! I’m guessing we eat about 1 percent of the varieties that are available — there are beets the size of volleyballs and carrots the size of daikon radishes. It’s staggering what’s out there that you don’t see.

The author of 18 books on edible landscaping, Rosalind Creasy uses her Los Altos garden as a trial space. She’s grown thousands of varieties over the years; below are some that she can’t do without.

'Bull’s Blood’ beets. This beet is spectacular in the garden with its burgundy leaves. The thinnings are lovely in a green salad and the beets are great baked.

'Cherokee Purple’ tomato. With luscious flesh and a rich, deep tomato flavor, it’s the most reliable of all the large fruited tomatoes in my garden.

'Christmas’ lima bean. This lima is the most reliable and productive I’ve ever grown. The plants are extremely vigorous and the beans are large and meaty.

'Five Color Silverbeet’ chard. It’s gorgeous in the winter garden, I arrange the colors in my beds to blend with flowers of the same color. This is my go-to winter vegetable.

'Forellenschluss’ lettuce. The delicate soft leaves are great in salads, and it performs well most of the year, even when it gets hot.

'Sheepnose Pimento’ pepper. I love this thick-walled pepper with its meaty flesh that’s filled with deep flavor. It’s great for roasting.

Growing from seed

Sowing seeds is easy. Here’s Creasy’s advice for beginners.

1. The most important part of starting plants from seeds is to read the directions on the package. Some seeds need to planted deeply, others might need to be planted shallowly. Don’t crowd the seeds when planting — follow the spacing requirements on the package.

2. After the seeds are in the soil, water very gently so you don’t wash the seeds out of place. Most importantly, do not to let the seed bed dry out. To speed the sprouting process for large seeds like beans, peas, squash and melons, soak the seeds in a container of water for a few hours before planting.

3. Beans of all types are the easiest vegetables for the beginning gardener, both for growing from seed, and for saving seeds for the next year’s crop. The seeds are large and are easy to handle, especially for children, and sprout easily.